Treatment of hydrocarbons



Dec. 21, 1937. G. EATON 2,102,947

TREATMENT OF HYDROCARBONS Filed March 27, 1934 frzveni or GeraldLJZ'aion his Alforney Patented 21, 193? UNITED STATES PATENT. OFFICETREATMENT OF HYDBQOAIIONB Gas. Eaton Philadelphia.

Process Corporation, Jersey City. poration of Delaware Application Marchat.

11 Claims.

This invention relates to the thermal conversion of hydrocarbons, andmore particularly to the production'from low-boiling hydrocarbons ofrelatively liigherboiling point hydrocarbons including hydrocarbonsboiling within the boiling range of commercial motor fuels and having.valuable anti-detonation characteristics and being otherwise suitableas motor fuel.

An object of this invention is to provide a 1. process wherebylow-boiling hydrocarbons, in-

cluding especially hydrocarboi'is which are nor mally gaseous, such asoccur in natural gas or in petroleum refinery gas, and particularly ingases from cracking still operations, may be conas constituents ofmotorv fuel. In accordance with this invention, the conditions createdand maintained in the several steps-are so adjusted- .and related as toeffect a maximum conversion of the hydrocarbons treated into desirableproducts and a minimum'conversion thereof into undesirable products. I

In the practice of this invention, the hydrocarham to be treated arecompressed prior to being subjected to heat and are maintained underpressure during the cracking operation and the polymerizing operation.The pressure maintained in the polymerizing step is essential to thepolymerisation desired; and compression before cracking avoids thenecessity for compressing hot uses between the cracking andpolymerizing.

steps, or, in the alternative, the hecessity for cooling, compressing,and reheating of the cracked gases at that point in the operation. Also,I have inventionI'the pressures. selected for promotion ofpolymerization are not'such as will deieteriously affect the progressand results of the, cracking operation; and the employ'mentof suchpressures 1934, Serial In the practice of this invention, lower boiling.

bans and preierably into hydrocarbons suitable j found that in procedurein accordance with this a in the cracking operation appears to minimize,

assignor, by

the formation of hydrogen to such extent as to render unnecessary theremoval thereof from products passing from the cracking operation to thepolymerizing operation; Moreover the employment of: pressure minimizesthe size of equip- 'ment necessary in apparatus employed in the practiceof my process. The pressure employed depends-upon and must bear a moreor less definite relation to other conditions adjusted in" accordancewith the principles of this invention,

the requirements of the polymerizing step in this regard being of greatimportance. To this end, pressures of the order of from per sq. in., andmore preferably pressures of the order of from 500 to 1500 lbs. per sq.inch, are employed in the practice ofthis invention.

In the practice of this invention, the conditions of temperature,pressure, and time employed inthe cracking operation areso co-ordinatedas to give definite results of" a particular. nature, and are soco-ordinated with the conditions preserved 200 to 3000 its.

and results effected in the polymerizing step that maximum production ofdesirable products with minimum production oi waste is achieved. Thus,the temperature, and time of the cracking operation are so chosen that,under the existing pres- I su e conditions, the content of unsaturatesand polymers in the products leaving the cracking operation will yield amaximum of desired polymers as a result of the polymerizing step, withminimum production of waste products. The

higher the temperature employed in the crack-- ing operation, the morerapid is the production oi fixed and inert gases and tar. The higher thetemperature employed, the greater is the concentration attainable-ofunsaturates plus polymers provided the durationof the high temperatureis correctly adjusted. Thus; for example, with a cracking temperature of1l00 F., em played in connection with a charge gas consistingprincipally of C: and C4 hydrocarbons", as high a content (percentage byweight) ,of unsaturates plus polymers cannot be achieved as can beachieved by employment of higher temperatures; at the lower temperatureit is not necessary to adjust the time with great care in order 'to ob-'tain the maximum concentration of unsat'urates plus polymers, anyperiod of time within a relatively wide range giving such maximumconcentration. On the other hand, when a temperature of i300 F.is-employed with such charge gas, the content of unsaturates pluspolymers .rises' to a higher maximumflaut the time must be adiusted withcare, because excessive time leads to rapid reduction of such content;and such exextends the production of waste products, such as inert gasesand tar.

' Accordingly, in the practice of this invention the relation of timeand temperature in the cracking operation is preferably so adjusted asto cause that operation to produce a maximum content of tion of benzol,whereas the preferable conditions in the practice of this invention areconducive to .the production of hydro-aromatic and cyclic hydrocarbons;and such hydro-aromatic and cyclic hydrocarbons have anti-detonationqualities, when actually blended with motor fuel,.which are in somerespects equal to if not greater than those qualities of benzol.

Inthepracticeof thisinvention the temperatures attained in the crackingzone are within the range of from approximately 1000' F. to 1500 F., and

more preferably from about 1200 F. to 1400 F.,

whenthe pressure maintained is of the order of from-200 to 3000 poundsper sq. inch,"and the duration of the elevated temperature is adjustedas above pointed out and hereinafter more specifically exemplified,suitable cracking periods being of the order of, for example, from 0.2to 0.5 second at 1350 F., or from 10 to 30 seconds while the temperatureof the hydrocarbons ll being raised from 1050 F. to 1200 F., when, forinstance,.a charge gas consisting principally of Ca and- C4 hydrocarbonsis being converted. Inasmuch as the employment of temperatures above theminimum at which cracking begins, results in the occurrence of crackingwhile the temperature of the hydrocarbons is being raised fromsuchminimum to the maximum temperature employed, account must be taken ofthe time required for that rise in' temperature as well as of. the timeduring which the-hydrocarbons are at the maximum temperature. Inpractice it is frequently advantageous to raise the temperature to apredetermined value and thereupon effect the cooling between thecracking and polymerizing operations; thus making it necessary to takeinto accountonly the time during which the temperature is rising froma-temperature at which substantial cracking occurs, e. g. rising from1050 F., up to. the predetermined maximum temperature. I

have found that the yield of unsaturates and the -yield of unsaturatesplus polymers decreases when, for a given cracking temperature, thecracking time is extended for too long a period, or when, forapredetermined heating period, the temperature is increased beyond theoptimum for that period. I have found that adjustment of the time andtemperature, at the pressure employed, in such relation as to produce amaximum concentration of unsaturates in thehydrocarbons leaving thecracking operation, facilitates a max imum yield of desired polymers anda minimum yieldof waste products, such asine hydrogen as to renderunnecessary the removal thereof from the system prior to thepolymerizing operation. I

Having completed the cracking operation, which involves an endothermicreaction and requires addition of heat, the polymerizing operartor fixedgases and tarfand results in such low content of,

r cessive maintenance of high temperatures also tion, which exothermic,is carried out; but I reduce the temperature of the gases passing fromthe cracking operation to the polymerizing operation. This reduction oftemperature slows down or annuls further cracking of the hydrocarbonstreated and tends to minimize or prevent further.

degradation of valuable hydrocarbons into fixed.-

or inert gases and tar or other waste products. Preferably, the coolingis eil'ected in such manner as to preserve such .pressure as is desiredin the subsequent polymerizing operation; and the cooling may beefiected by addition to the products passing from the cracking operationof a cooling, medium, such as naphtha, heavy oil; water, or inen. orhydrocarbon gas, or it may be effected by conventional heat exchange.The cooling will effect a reduction of temperature sometimes amountingto several hundred degrees, thus bringing the temperature of theproducts passing from the crackingzone at,,a temperature approximatelywithin the range of from 1000" F. to 1500 F., down to a temperatureapproximately within the range of from 700 F. to 1200 F., andpreferably.

within a range of mimetic" F. to 1050 n, the

pressure being maintained within the range of from approximately 200 to3000 lbs. per sq. in.

The desired polymerization may be effected with or without the aid of acatalyst, and the carrying out of this operation in a separatezonefacilitates the adjustment of temperature, time, and pressureconditions. The pressure, being of the order of from 200 to 3000 lbs.per sq. in., the time and temperature are adjusted somewhat as acompromise between theoretical and practical considerations. A longperiod of time at a relatively low temperature minimizes degradation andpromotes yield but requires apparatus of large capacity. At highertemperatures, polymerization can be effected more rapidly, butsimultaneous degradation is promoted. Inany event,,the polymerizationtends-to increase the content of p lymers and decrease the content ofunsaturates.

For example, when reaction-accelerating catalysts are not employed, ifthe charge gas consists principally of Ca and C4 hydrocarbons, and suchgas, under a pressure of substantially 1000 lbs. per sq. in., leaves thecracking zone with a 40% content by weight of unsaturates and thetemperature. of the polymerizing zone is held at 1000" 1''., for aperiod of from 4 to 8 minutes, a yield of 15% to 17% by weight of motorfuel hydrocarbons results, whereas if that temperature is held at 950 F.for a period of 8 to 15 minutes a yield of 17% to 20% by weight of motorfuel hydrocarbons results; if that temperature is held at 900 F., for aperiod of from 20 to 40 minutes, a yield of 21% to 23% by weight ofmotor fuel hydrocarbons results; and if that temperature is held at 800F. for a still longer period a still higher yield of such hydrocarbonsresults. The use of lower temperatures and longer times gives lessproduction of. hydrogen, methane, ethane,

V and tar. This example serves to indicate the conditions afl e'ctingthe choice of temperatures and pressures in the polymerizing operation,but in any event thepolymerizing operation usually requires periodsoftime measured in minutes as ends or, fractions of a second in thecracking operation. As a further example, when catalysts pressures ofthe order of 1000 lbs. per sq. in.,

whereas such time may be of the order of. from contrasted with periodsof time measured in secamass? about 2 to aboutfl minutes for ofabout'1000 It, the pressure being the same.

' In adjusting the temperatureand time condi tions for the pressureemployed, both in the cracking operation and the polymerizingoperationiit' is to be recognized that conditions employed in connectionwith hydrocarbon gas 0f onecomposition must be adjusted to eilectcomparable results in connection with hydrocarbon gas of a 'diilerentcomposition, higher content of hydrocarbons having a higher number ofcarbon atoms usually requiring lower temperatures and vshorter effectiveperiods of time.

In the practice of this invention, the products passing from thepolymerizing operation are subiected to cooling which condenses certainconstituents thereof, and the products may be separated into 'variousfractions, for example, iixed gases such as hydrogenand methane (andprefably-ethane), tar, desired polymers, and, gases suitable forrecycling through the system.

7 At point it will appear that practice in accordance with thisinvention provides for the 'production'of desirable liquid orliqueflable polymers from hydrocarbon mixtures which are ,whollyor inmajor proportion normally gaseous;

the desired products.

that the yield of desired products is high and thedegradation ofhydrocarbons isjminimized; that the advantages may flow from limitationof the conversion in the cracking operation while extending theconversion in the polymerizing operation; and that the co-ordination ofthe conditions in the cracking operation with those existing in thepolymerizing operation leads to an avoidance of extensive production ofhydrogen and inert gases and avoidance of resulting waste, andinterference with proper procedure toward To assist further in anunderstanding of this invention, there is described herein aspecificex-.

' ample oi the application-thereof, with the undervnection with thedescription thereof.

standing that this inventionis not limited thereto nor to the particularapparatus shown in con- Hydrocarbon gas, for example, such as that takenfrom an oil cracking unit, is passed from a source (not shown) throughvalve-controlled 'pipe' I tocompressor 2 wherein it is compressed to apressure of the ,order or from 200 to 3000 lbs./sq.in., and deliveredthrough valve-controlled pipe 3 totheicracking tubes 4 of memuses 0,Herein, the compressed gases are heated to a temperature of from about1000 F. to about 4500 F., for a period of time suillc'ient to efiect asubstantial conversion of the stable constituents of. the gas topolymerizable. :unsaturates. The heated products from the cracking tubes4, at a temperature of from substantially 1000, F. to 1500 FL, and undera pressure of the order of from 200 to 3000 lbs./sq.in., are passedtostransforum 6, and thencaintqreaction chamber'll However, eitherduring their passage through the transfer line or at their point ofintroduction into the reaction chamber, the heated products are cooledfrom a temperature of the order of from.

1000 F. to 1500 F., to a temperature of from substantially 700 F. to1200 E, whereby further is substantially prevented. The step v oi!cooling may be accomplished in various ways.

example, -ajportion or the coyipressed' hydroam-mm; I. in closed may bepassed through pipe ier ai-v ve-controuea pipe l0 and pipe u transfer-.line' 8, valves l2 and I! being recycle hydrocarbonsmay be intmduced'E'-into line I from valve-controlled 1 and pipe 28 may be redu d by meansof valve 22, for example, from about 200 to'about. 3000 lbs./sq.in.,

pipe It, or a cooling medium such as, for example, inert gas,hydrocarbon gas, naphtha,

heavy oil, water or steam may be passed, under pressure, from a supplynotshown, through valve-controlled pipe I! and pipe ilinto transfer line6."; Cooling of the heated products from the cracking tubes [may beeilected, I: desired, by a the installation of conventional heatexchange,

apparatus in the transfer line 0. Regardless of the cooling means used,the temperature of the heated products is reduced to the order of fromabout-700915. to about 1200 F., at which temperature further cracking issubstantially prevented and at which polymerization-is effected. .Thethus cooled productsin thereactlon chamber I are maintained at atemperature of from a about 700 F. to about 1200 F. and under a pressureof from substantially 200 to 3000 lbs./sq. in.,

for a period of time suiiicient to eifect the most economical degree ofconversion of.the unsaturates into desirable polymers. The products fromthe reaction chamber 1 are passed, by

'means of valve-controlled pipe I and pipe i5 into separator l6. Incertain instances, it may and water vapor if present, are passed fromthe top of the separator W at a temperature prefer ably below 800 F.,through valve 22', cooler 23 to water separator 25. Pressure to about200 to 1000 lbs/sq. in., and the temperature of the vapors passingthrough cooler 23 may .be' reduced fromabout 800 F. or lss, to

' about from 35 F. to 250 F., thereby permitting 'the bulk oi the water,when present, to separate from the hydrocarbons, said water beingwithdrawn from the separator 25 through valve-comtrolled pipe 26. v

g The hydrocarbon mixture comprising polymers, unconverted hydrocarbons,fixed gases and a small quantity of-tar is passed from the waterseparator ,25 through pipe 21 into reflux column 28 provided adjacentits top with a refrigerating coil 29. In the column 28 the hydrocarbonliquids are freed or the fixed gases, i. e., hydrogen and 'methane (andpreferably also ethane) which are removed from the top of the column bymeans of pipe 30 and vented through valve 3!, the coil 29 providingreflux which aids in the removal of,

higher boiling hydrocarbons from the gases. The hydrocarbon liquidwithdrawn from .the' bottom of column 20 is forced, under a pressure ofthe order of from about 200 to 1000 lbs./sq. in. through heatexchanger", wherein-the temperature is raised to about from 100 to 500F. The heated hydrocarbon mixture is passed from 'the' exchanger 32through valve-controlled pipe 33 into fractionating column 04, providedwith a heating coil 46. The pressure on the hydrocarbons introduced intocolumn 34 is preferably reduced from about 200 to 1000 lbs/sq. in., toabout 50 to 400 lba/sq. in., by means of valve 83', the temperature ofthe material introduced into the column being .within the range, forexample, of from about 100 F. to about-500 1". 'Incol'umn.

34 the normally gaseous hydrocarbonsare fracf .tionated from thepolymersand tar, theformer being removed from the top 'of thecolumn 1throughs-pipe l6 and passed into partial condenser 31, from which anyliquid condensed is withdrawn and returned to column 34 by means ofvalve-controlled pipe 38, pump 39a and valvecontrolled pipe 38b, to'serve therein as reflux. The uncondensed gaseous hydrocarbons areremoved from the top of partial condenser ll and v are passed through vve-controlled pipe; 39 to compressor 40. The condensed gases arecompressed therein to a pressure of the order of from about 200 to about3000 lbs/sq. in., and may be a pressure of from atmospheric to 200lbs/sq. in. 7

recycled by means of pipe 4! and valve 42' to the cracking tube 4 forfurther heat treatment, or they may be passed, under the aforesaidpressure.-

through pipe 43, cooler 44 and valve-controlled pipe i3 into transferline 6 to function as a coolant for the heated products from thecracking coil 4.

In the event that the recycling of theunconverted hydrocarbon gases isnot desired, said gases may be vented by means of valve-controlled pipe39a.

The polymersand tar from the bottom of column 34 are passed underpressure, through pipe 45, valve 46, heat-exchanger 4'! and pipe 48 into1 fractionating column 49, provided withheating coil 50. This column isoperated preferably at a. temperature of from 200 F. to 500 FJ, andunder Herein the polymers and tar are separated by fractionation. Thepolymers are removed as vapors from the top of the columnthrough pipe 51and passed to condenser 52 wherein condensation is effected, a portionof the liquid polymers then being returned as reflux to column 49bymeans of valve-controlled pipe 63, and the remiainder of the polymersbeing withdrawn to storage through valve-controlled pipe 54. Taris drawnfrom the bottom of column by means of valve-controlled pipe 55, and isremoved from the system through pipe 20 and valve 2|.

While in the above illustration I have'shown a reflux tower (28) as ameans of separating the fixed gases from the valuable hydrocarbons, Imay substitute therefor, a flash drum wherein the un-' condensed gases,in equilibrium with the liquid hydrocarbons, may be separatedtherefrom,- under the proper conditions of temperature and prasure.Likewise, various modifications in the fractionating column 34 may beemployed, or a different type of fractionating equipment, such as forexample, an absorption system, may be utilized in place of columns and34. In general. the separation of the. products of reaction may-v beaccomplished by variousmeans familiar todefinedas that material boilingbetween 60 F.

and 400 F. Tar? is designated as material boiling above 400? F.

'; Example 1.-'-.1vo catalyst I Pressure perv. a (m/sq. im a.) Contacttime cm cns 'maflhu- 1200 s 1 -10 206 0 r.

'Polym eri'zingzonam 900 I :90 wminut es.

Analyses Chsrgeto Leaving crack- Leavingpolycracking lone ing zonemcrizing zone Wt. .Vol. Wt. Vol. Wt. Vol. perperperpcrperper. cent centcent cent cent cent ydrogen 0.2 2.7 0.2 as Methane l2. 0 26. 4 l4. 9 33.6 Ethylene 5. 9 7. 4 2.2 2.8 Ethane 1.0 1.6 9.0 10.6 11.4 13.7 Propylene12. 1 10. l 4. 3. 8 Propane... 64.0 69.5 37.3 29.9 33.6 27.5 Butylane Y4.7 3.0 1. 7 1.1 Butane 35.0 28.9 12.8 7.8 11.5 7.1 Nnnhfim 0. 0 2. 017. 1 0. 3 Tar--- 0.4 0.1 3.0 0.0 'fotal 100.0 1000 100.0 1000 100.0100.0 Total oinns...- 22.7 20.5 8.4 7.7

Example II.-No catalyst Temper'a- Pressure Contact ture (lbs/sq.in.-ga.) time F: g

Cracking zone. I 1300 500 0.4 second. Polymerizing zone-.. 900 60050minutes.

Analyses Ghsrgetov Iaavingcrack- Leavlngpolycracking zone ing zonemerlzing zone we v01. Wt. v01. Wt. v01. W- p 0 perp cent cent cent centcent cent 02 4. 0 0. 2 4. s 1.1 5.4 1&0 8.7 23.0 I. 7 6.2 B. 6 1. 6 2.47.2 7.6 9.8 10.3 14.6 14.0 2Z9 19.2 5.2 6.2 46. 7 34. 9 39. 5 30. 9 29.7 Butyiene---- 104 9.5 6.6 2.4 1.8 Butano 18. 9 8. 9 5. 9 7. 9 5. 8Naphthn 0. 1 2. 4 2s. 0 12. 1 Tar.-. 0. s 0.1 4. a 1. 0 "Total. 100.0100.0 100.0 100.0 1000 100.0 'lt oiiiolaanamua... 20.5 20. 30.0 314 0.20.4 3 J I In Example I the charge was of natural gas source, andcontained no unsaturates. The obiect ofthe thermal treatment inthecracking zone was to produce'the maximum percentage of ole ns'plusnaphtha, with the minimum productio .of hydrogen, methane,- and ethane.The

contact time given isapproximately the optimum for the temperatureemployed. In this case the gas was heated continuously to a furnaceoutlet temperature of 1200 -F., and the contact time tabulated isthetime in which the gas was heating fr0m.1050 F.'to 1200 F. f I

Had the contact time at this temperature been either substantially lessor substantially greater than that given, the conversion would not havebeen as satisfactory, since the amount of oleflns plus naphtha wouldhave been less than that tabulated. Also, if the time had been longer,the

amount of hydrogen, methane, and ethane would have been greater. Bycooling immediately to the polymerizing temperature, after .the propercracking time, the production of naphtha in the process as a whole ismarkedly increased.

In Example II the charge was of refinery gas 7 merizing zone, and ifrecycling or these unconverted compounds is ed out quantitatively, inExample'I the ultimateyield of naphtha would be of theorder of 35% byweight as against a once thru yield of 17.1% by weight; whereas inExample 11, the ultimate yield of naphtha would be of the order of 47%by weight, as against aonce thru yield of 23% by weight.

One of the. major advantages of my process consists in the fact that theentire stock is treated under the optimum conditions, so that by con-.trolling the time of reaction the greatest ratio of valuable products towaste products is obtained. Under these conditions there remainconsiderable unconverted compounds which may again be passed through theapparatus to obtain the same high ratio of valuable to waste products.

' Had the conversion been carried on for-appreciably longer crackingtimes than the optimums disclosed herein, the once through yield ofnaphtha would have been slightly greater, but the ultimate yield wouldhave. been very markedly reduced.

with regard to the function of pressure in the ,two stages of myprocess, I find, in the cracking zone, that pressure has relativelylittle eilect on the reaction other than itsefiect on contact time. Inthe polymerizing zone, however, the polymerization of unsaturatesto.naphtha. is very greatly aiiected by pressure, particularly in the rangebelow 200 lbs/sq. in., and unless the pressure is above this figure onlyslightconversion is obtained, in the absence of catalysts.

For brevity, herein and in the appended claims, the term cooling mediumis to be understood to comprehend such agents as hydrocarbon oil;-compressed hydrocarbon gases, water and steam. Also, when'in theappended claims the term a high superatmospheric pressure is employed,it

is to be understood to mean pressures of the order of 200 lbs/sq. in. orgreater. What I claim is:

1. The process of converting predominantly paraillnic normally gaseoushydrocarbons into polymers, which comprises heating said hydrocarbonsunder a high superatmospheric pressure to a temperature at which atleast a portion of said hydrocarbons will decompose to form substantialquantities of unsaturates, cooling the heated products to a temperatm'eto prevent further substantial decomposition and at which polymerizationthereof takes place, introducingsaid cooled products without separationand while maintaining substantially the same pressure into a reactionzone wherein polymerization is eirected during the passage ofsubstantially all or the cooled products therethrough, and removing theproducts of reaction from the zone last mentioned.

2. The process of converting predominantly polymers, which comprisesheating said bydrocarbons under a high super-atmospheric pressure to-atemperatureat which at least a portion of tion'ed, iractionally'separating the products of re- [cooled products therethrough removingthe. products oi. reaction from the zone last men action, and recycling.unconverted hydrocarbons for further heat treatment.

8. The process oi converting normally gaseous hydrocarbons intopolymers, which comprises heating said hydrocarbons under a highsuperatmospherlc pressure to a temperature of the order of'trom 100051to 1500' F., whereby at least a portion of said hydrocarbons willdecompose to form substantial quantities of unsaturates,

cooling the heated-products to a temperature 0! the order of'from 700 F.to 1200 F., to prevent further substantial'decomposition and at whichpolymerization thereof takes placefiintroducing the cooled productswithout separation and whilemaintaining substantially the same pressureinto a reaction zone wherein polymerization is eflected during thepassage of substantially all or the cooled products therethrough, andremoving the products oi. reaction from the zone last men.-

tioned. a

4. The process or converting predominantly paraflinic normallyigaseoushydrocarbons into polymers, which comprises heating said hydrocarbonsunder a high-superatmospheric pressure to a temperature at which atleast a portion of said hydrocarbons will decompose to form subheatedproducts to a temperature to prevent fur:- ther substantialdecomposition and at which polymerization takes place byintroducing-there-' into a cooling medium, passing said cooled products'without separation and while maintaining paraflinic normally gaseoushydrocarbons into polymers, which comprises heating said hydrocarbonsunder a high superatmospheric pressure 'stantial quantities ofunsaturates, cooling the' to -a temperature of the .order of from 1000F. to

1500 F., whereby at least a portion of said hydrocarbons will decomposeto form substantial quantities of unsaturates, cooling the heatedproducts to a temperature of the ordrbf from 700' I". to 1200 F., toprevent further substantial decomposition and at which polymerizationtakes place by introducing thereinto a cooling medium, passing the.cooled products without separation and while maintaining substantiallythe same pressure into a reaction zone wherein polymerization iseffected during the passage of substantially all of the cooled productsthere-' polymers, which comprises heating said hydro carbons under ahigh superatmospheric pressure said hydrocarbons will decompose, to formsubstantial quantities of unsaturates, maintaining such temperature andpressure conditions for such time as will give in .-the products leavingI the cracking operation substantially the maximum content of. polymersplus unsaturates attainable at such temperature, cooling the heatedproducts to a temperature to prevent further 'substantial decompositionand at whicly polymerization thereof takes place, introducing saidcooled products without separation and while maintaining substantiallythe same pressure into a reaction zone wherein polymerization iseffected during the of substantially all of the cooled productstherethrough, and remov ing the products of reaction from the zone lastmentioned.

7, The process of converting predominantly paraflinic normally gaseoushydrocarbons into polymers, which comprises heating said hydro-' carbonsuiinder a high superatmospheric pressure to a te perature at which atleast a portion of said hydrocarbons will cdecompose to form substantialquantities of unsaturates, introducing a part of the hydrocarbons fromthe same source asthose being heated into contact with heated productsto cool them to a temperature to prevent further substantialdecompositibn and at which polymerization thereof takes place,introducing said cooled products without separation and whilemaintaining substantially' the same pressure into a reaction zonewherein poly merization' is eifected'durins the e of substantially all.of the cooled. products therethrough, and removing the productsofreaction from the zone last mentioned.

8. The process of converting predominantly paraflinic normally gaseoushydrocarbons into polymers comprising motor fuel, which 'co'm-, prisesheating saidhydrocarbons under a high to a temperature at which at leasta portion of"? tained at a high superatmospheric pressure whereinpolymerization is effected during the passage of substantially all ofthe thus cooled products therethrough, and removing the prod-' ucts ofreaction from the reaction zone to recover polymers-therefrom.

9. The process of converting predominantly paramnic normally gaseoushydrocarbons into polymers, which comprises heating said hydrocarbonsunder a pressure in excess of about 500i stantially, the same pressureinto a reaction zone wherein polymerization is effected during thepassage of substantially all of the cooled products therethrough, andremoving the products of reaction from the zone last mentioned.

10. The process of converting predominantly parafllnic normally gaseoushydrocarbons into polymers comprising motor fuel, which comprisesheating said hydrocarbons under a high superatmospheric pressure atleast as great as that later mentioned for the reaction zone to atemperature at which at least a portion of said hy-' "drocarbons willdecompose to form substantial quantities of unsaturates, cooling theheated products to a temperature to prevent further substantialdecomposition and at which polymerization thereof takes place,introducing substantially all of said cooled products without separationthereof into a reaction zone maintained at a pressure in excess of about500' pounds per square inch*wherein polymerization thereof is effectedduring the e of substantially all of the thus cooled productstherethrough, and removing the products of reaction from the reactionzone. to recover polymers therefrom.

rates.

' GERAID L. EATON.

